Combined fuel measuring pump and fuel feed valve for internal combustion engines



Patented June 1931 PATENT OFFICE UNITED STATES my am ram, or BROOKLYN, NEW YORK EBIN'ED FUEI; IEASUBIIN'G PUMP IAND FUEL FEED 'VALVE FOR (XIMIBUSTION ENGINES y Application led September 30, 1926. Serial No. 138,300.

My invention relates to a combined fuel measuring'pump and fuel feed valve for internal combustion engines for measuring and injecting liquid fuel at high, pressure,

Without the use of compressed air, directly into the cylinder of internal combustion engines.

The general object of my invention is to provide a device of the indicated purpose in which the fuel valve and fuel measuring pump are combined in a single unit whereby various advantages result as will appear.

The nature of the invention and its distinguishing features and advantages will be clearly understood as the description pro-k ceeds.

Reference is to be had to the accompanying drawing forming part of this specification, in which the figure represents a vertical section of a combined fuel measuring pumpand fuel feed valve embodying my invention, it being understood that the drawing'is merely illustrative of one example of the invention.

In carrying out my, invention in practice a5 in accordance with the illustrated example the device includes a body `10 having at one end thereof a fuel discharge opening or openings 11, here shown as infa separate element 13, held by a cap 12. Element 13 is formed 3o with a suitable valve seat 14. Extending upwardly from the valve seat 14 is a fuelfeed passage 15 in which operates a spindle valve 16 having an enlarge upper end 17 to provide an enlarged zone 18. The passage l5- communicates at the top with a chamber 19 having a fuel inlet 20. Set also at the top is a bleeding cock 21 or equivalent bleedingmeans. Bearing on the upper end of fuel valve 16 is a separate cap 22 under the pressure of a spring 23 coiled about the stem or reduced end 24 of aplu 25 which screws vinto the body 10, closing te Vchamber 19 at the top.v v A A measuring and force pump plunger 26 extends into a fuel passage 42"("having a side inlet port 28A from chamber 19 and thereby adapted to receive fuel delivered to said chamber 19 from inlet 20. Pumpplunger 26 has a head 29 against which bears a spring 30 coiled about said plunger 26. -Spring30 and head 29 operate in a chamber 31 into which the plunger 26 extends. The numeral 32 indicates a drain cock for chamberl 31. The plunger 26 is subject to Va reciprocating movement of a tappet 33 operated by a suit- 55 able cam device 36 here conventionally shown, said cam device operating against the head 34 of tappet 33. Spring 35 bears against head 34 and against body 10, tending to lift the tappet 33 when permitted to do so by the revolution of the cam 36. Liquid fuel is supplied at a moderate pressure of 25 to 30 pounds to the square vinch through inletr 20, thereby filling the chamber 19 as well as the passages 27 'and 15. Any air carriedin with the fuel or trapped in the interior of the device will rise'to the upper partof chamber 19 and may be bled oii" to the atmosphere by means of the cock 2101` other bleeding device. Pump plunger 26, upon being moved toward passage 15 u nder pressure of tappet 33 andcam device 36 will close the port 28, thereby"` causing an immediate rise in the pressure of the liquid fuel trapped in the passages 27 and 15. The increase of pressure lifts the fuel valve 16 away from its seat 14 by reason of the different diameters at the end of the fuel valve and at the zone 18. The continued movement of the plunger 26 at closing port 28 will force the liquid in the passages 27 and 15 through the discharge openings at 11, and into the engine cylinder. The plug 25` and its stem 24 act as a stop to limit the upward movement of the fuel valve 16. As will readily be understood the pressureat the point of discharge into the cylinder at the opening 11 is determined by the size of said opening at 11 and the tension of spring 23. The finely atomized ]iquid fuel emerging from the opening l1 into stood, be ignited by the heat of combustion alone, as'in the high compression Diesel type of engine or by a heated surface as in the medium compression, surface ignition, semi-Diesel engine, or by an electric sparking device as in a gasoline engine. The described assemblage functions in a manner that the various passages of the fuel chamv ber proper and the fuel valve chamber automatically clear themselves of entrained air `in the fuel, as the air Will rise in theiupper part of the chamber 19 where it will not afthe pump plunger 26 is withdrawn and un- -not affect the o covers said port 28.

During the revolution of the cam device`36 Y the tappet 33 will be relieved of the cam pres- A sure and will allow'said tap et 33 and plunger 36 to be moved outward y the springs 30 and 35, which will result in a drop in the pressure of the fuel in the passa es 27 and 15. The drop in pressure 1n sai passages 27 and 15 allows fuel valve 16 to be returned to its -seat 14 by the sprin 23. The continued upward movement/o? pump plunger 26 causes a partial vacuum 1n the passages 27 vand 15, until port 28 is uncovered, when the vacuum is broken and said passages are again filled withfuel from the said chamber 19.

The advantages of the above describedv assemblage will be apparent, as follows:

It combines fuel valve and fuel measuring pump in a single unit; it eliminates the massive and costly measuring pumps generally used; the device may be cheaply and m'mply manufactured; the use of a checkvalve as commonly used in the fuel pump is eliminated; all high pressure 'piping connecting fuel measuring pumps and fuel valves as ordinarily arranged is eliminated; no high pressure is developed in the device except during the delivery stroke of the ump; the pressures possible of attainment or injecting the fuel are much hi her than in the systems usually employed; pressures cause the fuel to break up and be more finely atomized upon its escape into the cylinder, thereby giving better combustion; the danger of those parts subjected to high pressure leaking or bursting is eliminated; fuel valve 16 operates quickly, cutting offthe fuel jets at the discharge opening 11 sharply upon the valve closing, which prevents the forming of a drop at the discharge opening with the effect of after burning; which is the case. when the common type of slow-closing fuel valve is used; the device eliminates the trouble caused. by air pockets so common in. systems ofl this general character, because even though considerable air might collect in the upp'er part of the chamber 19 it would ration of the pump plunger; the amount o fuel delivered is easily controlled by varying the amount of inward movement-of the pump plunger 26 b suitable variation in the cam motion of the evice 36;

the device is particularly suitable for very small cylinders, as it will measure and deliver small quantities of fuel accurately; the fuel valve 16 is lifted well away from its seat 14.-,

4is a common trouble in the .present vand a e higher Lerma thus preventing the cutting of the seat by the high velocity ofthe owing fuel, which stems; the device will o crate quite success y at high speed; and ally, it will not easily get out o f adjustment, Aas is the casewith systems DOW 1n USG.

In the operation of the` device, the passages and 27 constitute the measuring chamber. l t

' I would state furthermore Ithat while the illustrated example constitutes a practical embodiment ofmy invention, I do not limit myself strictly to the exact details herein illustrated, since, manifestly, the Same canv be considerably varied without departure from the spirit of the invention, appended claim.

What I claim is:

A combined fuel measurin pump andl fuel feed valve for internal comustion engines, comprising abody having a vertical portion, a suppl chamber in the upper part thereof `schal-ge chamber in the lower part thereof, an integral angularlyrelatedportion containing vapressure chamber commuas defined in the .nicating with said supply and, discharge chambers and also containing a recess located above said pressure chamber, a plun er slidably mounted in said pressure cham er and extendingintc said recess, said plunger having a shoulder, a coil spring on said plunger and bearing against said shoulder, means for actuating said plunger, an oil bleeder valve communicating/with the lowermost part o f the recess, an air bleeder valve communi-y cating with the uppermost part of said supply chamber, a supply tube communicating with said supply chamber, a valve located in said discharge chamber and having a smaller diameter than said chamber, an enlar ed portion of said valve extending into sai supply chamber and meansv for urging the valve to closed position.

VERN `:REED PETTY. 

